The Leyden LectureProfessor Goldscheider, the oldest and the most distinguished pupil of Leyden, delivered the Leyden Lecture this year (subject, neuroses), which was established by the Berliner Verein für innere Medizin und Kinderheilkunde, in honor of the eminent clinician. Neuroses, according to Goldscheider, are disturbances in the functioning of the nerves. They produce symptoms but do not cause anatomic changes in the tissues. Organic disorders are often associated with disturbances of nerve function. These may disappear without any changes in the anatomic manifestations; the change in their symptoms cannot be made to harmonize with the changes in the tissues. The interaction of physical and mental processes is responsible for the genesis of neuroses. From this point of view a sharp differentiation between psychoneuroses and neuroses cannot be drawn. A hypersusceptibility of the nerves is an entirely plausible assumption as a physical basis for the causal mechanism of neuroses. For